DOS Fn 4409H: IOCTL Is Drive Remote or SUBST

                                                         Compatibility: 3.1+ 
 Expects: AX    4409H
          BL    drive number (0=default, 1=A, 2=B, etc.)
 Returns: AX    error code  if CF is set to CY
          DX    Bit 12 is 1: Drive is remote  (if no error)
                Bit 12 is 0: Drive is local and DX=IoctlDriveInfoRec
    Info: Obtains information about a drive, including whether or not it is
          remote (on the network).  For local drives, this returns
          additional information including, which IOCTL fns it supports,
          and whether the drive is a logical drive created by the Subst

          On return, DX bit 12 (DX & 1000H) is 1 if the drive is remote
          (i.e., on a network server) and all other bits are 0.

          See IoctlDriveInfoRec for a layout of the flags returned in DX
          when bit 12 is 0 (i.e., not a remote drive).

   Notes: ■ This is the only way to see if a logical drive ID represents a
            Subst drive.  It also lets you see if a local drive is shared
            by others on the network.

See Also: Fn 44H (IOCTL)
          Fn 440AH (Is File/Device Remote)
          DOS Functions